The present invention relates to network management in communications networks and particularly, although not exclusively, to manipulation and reconfiguration of routes taken by trails in a communications network.
In the applicant""s co-pending US patent application entitled xe2x80x9cDetection of Network Topology Changes Affecting Trail Routing Consistencyxe2x80x9d filed concurrently with the present application, there is disclosed a method and apparatus for detecting client layer trails which become unsupported due to reconfiguration of a communications network at a server layer, or proposed reconfiguration of a network at a server layer. Modification of physical or logical links in a network affect one or more client trails dependent upon those links for their existence and functioning. There is also disclosed a method and apparatus for finding alternative routes for unsupported client layer trails resulting from topological changes to server layer links. Detection and routing algorithms operate on information maintained in a managed object database subject of the applicant""s co-pending U.S. patent application Ser. No. 09/010387 filed at the US Patent Office on Jan. 20, 1998 and entitled xe2x80x9cCapability Modeling Using Templates in Network Management Systemxe2x80x9d, the contents of which are incorporated herein, and in which a managed object database representing individual physical and logical resources of a network is automatically updated to reflect actual changes to the physical resources which occur in a network by transmission of compressed data over an operation administration and maintenance (OAM) channel to a centralized or distributed network controller.
Changes to network resources which result in client trails becoming unsupported, or proposed new trails being in conflict with existing trails result in a detection algorithm operating to set a state of an instance of an affected physical or logical resource to a set of states including an xe2x80x9cinconsistentxe2x80x9d state, an xe2x80x9cin conflictxe2x80x9d state, and a xe2x80x9cdeleted supportingxe2x80x9d state, which are described in the applicant""s co-pending U.S. patent application Ser. No. 09/014742 entitled xe2x80x9cState Machine for Trail Management Systemxe2x80x9d filed at the US Patent Office on Jan. 20, 1998, the contents of which are incorporated herein.
Although the above disclosures provide a mechanism for automatically receiving data describing changes to a network and updating a managed object database, and for detecting changes to a network and generating data describing proposed re-routing of trails, the above disclosures do not go as far as actual implementation of new routes of trails and manipulation of trails resulting from changes in network topology or operational requirements.
One object of the present invention is to automatically implement re-routing of trails in a communications network, in particular re-routing which becomes necessary or desirable as a result of topological changes to a network, for example addition or deletion of a node entity.
According to a first aspect of the present invention there is provided a method of reconfiguring a plurality of trails in a network comprising a plurality of network resources, said method comprising the steps of:
storing a plurality of objects representing individual ones of said network resources;
for each said object representing a trail across said network, modifying a set of pointers of said trail object to point to a plurality of other said objects representing endpoints, connections and network elements, for defining said trail; and
reconfiguring said network resources in accordance with said trail object for implementing said trail in said network.
Said trail may be implemented in said network by adding or removing said trail, re routing said trail or partially removing or adding said trail.
Said step of altering said pointers of said trail object to a plurality of end points may comprise altering pointers to point to a set of sub-network connections which connect connection termination points and trail termination points and/or to a set of link connections which connect connection termination points.
According to a second aspect of the present invention there is provided a method of reconfiguring a trail extending over a plurality of network elements in a communications network, to incorporate a further network element in said trail, said method may comprise the steps of:
creating a first endpoint at said further network element;
creating a second endpoint at said further network element;
creating a sub-network connection between said first endpoint and said second endpoint at said further network element;
connecting a first link from a first of said plurality of network elements to said further network element; and
connecting a second link between a second one of said plurality of network elements and said further network element:
According to a third aspect of the present invention there is provided a method of reconfiguring trails in a network, wherein and after said reconfiguration, said first trail extends between said first and second network elements and a new trail extends between said third network element and said second network element said method comprising the steps of:
disconnecting a pair of endpoints supporting said first trail at said third network element;
modifying said first trail on said third network element; and
creating said new trail between said third network element and said second network element.
Preferably said step of creating a new trail between said second network element and said third network element comprises utilising at least one end point and at least one sub-network connection of said first trail.
Said step of disconnecting a pair of endpoints at said third network element may comprise disconnecting a sub-network connection from a connection termination point.
The method may further comprise the step of for each of a plurality of client layer links supported by said first trail, setting a plurality of corresponding link termination point to said third network element.
The method may further comprise the step of creating a plurality of client layer links extending over said second trail between said third and second network elements.
According to a fourth aspect of the present invention there is provided a method of reconfiguring a trail extending over a plurality of network elements from a state in which said trail extends between a first network element and a second network element via a third network element, to a state in which said trail extends between said first and second network elements without traversing said third network element, said method comprising the steps of:
extending a first link connection initially extending between said first network element and said third network element to extend between said first network element and said second network element;
removing a plurality of end points at said third network element from said trail;
removing a sub-network connection at said third network element from said trail;
removing a link connection between said third network element and said second network element from said trail.
According to a fifth aspect of the present invention there is provided a method of reconfiguring trails extending over a plurality of network elements, wherein in an initial state, first and second trails extend between first and third network elements and third and second network elements respectively, and in a reconfigured state, said first trail extends between said first and second network elements via said third network element, said method comprising the steps of:
making a connection between an endpoint of said first trail at said third network element and an endpoint of said second trail at said second network element; and
adding said connection to said third network element.
The method may further comprise the step of removing an endpoint of said first trail at said third network element.
The method may further comprise the step of deleting said second trail between said third node element and said second node element.
A link connection between said third node and said second node to said third trail.
The method may comprise the step of defining a trail termination point for said first trail at said second node.
The method may comprise the step of adding a sub-network connection at is said second node to said first trail.
The method may comprise the step of providing at least one client link between said first node and said second node.
The method may comprise the step of deleting a client link dependent on said second trail between said third and said second nodes.
The invention includes a method of reconfiguration of client trails from a configuration wherein a first client trail extends between first and third nodes and the second client trail extends between said third node and a second node, to provide a reconfiguration in which said first client trail extends directly between said first and second nodes, said method comprising the steps of:
disconnecting said first client trail from said third node;
connecting said first client trail to said second node; and
creating a sub-network connection at a server layer of said first and second client trails, between first and second server link connections.
The method may further comprise the steps of removing at least one other un-reconfigured client trail related to the first and/or second client trail.